CVE-2026-48020
CVE-2026-48020 updated by NVD
Summary
Traefik is an HTTP reverse proxy and load balancer. Prior to 2.11.48, 3.6.19, and 3.7.3, there is a high severity vulnerability in Traefik's StripPrefix middleware that allows an unauthenticated attacker to bypass route-level authentication and authorization. When a public router matches on a PathPrefix rule and applies the StripPrefix middleware, a request path containing .. or its percent-encoded form %2e%2e can match the public route at routing time and then, after the prefix is stripped and the path is normalized, resolve to a path served by a separate, authenticated router. As a result, an attacker can reach protected backend paths — such as admin or internal configuration endpoints — without satisfying the authentication middleware attached to the protected router. This vulnerability is fixed in 2.11.48, 3.6.19, and 3.7.3.
Affected packages
| Ecosystem | Package | Affected versions | Fixed versions |
|---|---|---|---|
| Go | github.com/traefik/traefik/v2 | — | 2.11.48 |
| Go | github.com/traefik/traefik/v3 | — | 3.6.19, 3.7.3 |
Remediation: Upgrade to 2.11.48 or later.
References
Includes data from the GitHub Advisory Database, licensed under CC-BY 4.0.
Includes data from the National Vulnerability Database (NIST). NVD data is in the public domain; this page is not endorsed by NIST.
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EPSS scores provided by the FIRST.org Exploit Prediction Scoring System.